Vascular changes in duodenal mucosa in shigellosis and cholera.

Vascular endothelial cells are highly specialized cells with numerous sensory and modulator functions. Our previous studies show extensive microvascular changes in rectal mucosal vasculature of patients with acute infective diarrhea (Mathan and Mathan 1985a, Gut 26:710-717). We looked for changes in the duodenal mucosal vasculature in two naturally occurring diarrheal infections: shigellosis and cholera. Duodenal mucosal biopsies from 14 patients with shigellosis, 12 patients with cholera, and 10 healthy volunteers were examined under the electron microscope. There were extensive microvascular changes in the duodenum in shigellosis and cholera. Congestion and dilatation of capillaries and venules, stagnation of blood, thinning of the endothelial lining, and platelet clumping were commonly seen in both conditions. Endothelial damage was also common to both conditions but was mild to moderate in cholera and severe in shigellosis with frank hemorrhage, frequent formation of stress fibers, widening of intercellular spaces, cytoplasmic blebbing, cell fragmentation, and intravascular thrombosis. Erythrocyte aggregates, platelet aggregates, and leucocyte plugging lead to capillary obstruction. The arterioles were severely constricted. These changes in the endothelial lining of the microvasculature could contribute to the pathogenesis of the disease resulting in peripheral vascular insufficiency, inadequate oxygen delivery to intestine, and organ dysfunction. The factors influencing these changes, their implications, and possible therapeutic interventions are discussed.